1. Field of the Invention
The present invention generally relates to wire harness units utilized in automotive vehicles. More specifically, the invention relates to slack absorption in a wire harness unit during the installation of an electrical component in the automotive vehicle.
2. Description of Related Art
Wire harness units are used in many applications in an automotive vehicle. For example, in order to connect a head unit (the unit comprising the vehicles audio/entertainment/navigation systems) to the electrical system of the vehicle, a connector on the end of the wire harness unit is drawn out from behind the instrument panel, through the opening in which the head unit is to be installed, and connected to the head unit. In order to be able to draw out the connector a distance sufficient to allow it to be connected to the head unit, a certain amount of slack must be provided in the wire harness unit. While allowing the extending of the wire harness unit for installation purposes, this slack can pose a subsequent problem when the head unit is moved into its installed position.
To install the head unit, head unit is moved forward (toward the forward end of the vehicle) into the opening through which the connector was previously drawn out. The slack of the wire harness unit is therefore reintroduced into the area behind the instrument panel. The area behind the instrument panel, however, is increasingly occupied by additional and other componentry. As a result, space within this area is at a premium, and any slack in the wire harness unit may result in the wire bundle of the wire harness unit becoming entangled with other componentry or may result in the wire bundle impinging on other componentry and either becoming pinched or impairing the installation of the head unit. For this reason, controlling or absorbing the slack in the wire harness unit must be taken into account.
One means by which the slack in a wire harness unit is absorbed is by providing a slack absorbing apparatus or guide. The slack absorbing apparatus is typically a plastic part with a receptacle that accommodates a coiled or curved portion of the wire bundle of the wire harness unit such that as the wire bundle is drawn or pulled out for connection to the head unit, the coiled portion is similarly drawn out of the plastic part. When the wire bundle is inserted or pushed in during installation of the head unit, the wire bundle is forced into the receptacle of the plastic part where it is supported and the slack is prevented from sagging and/or impinging upon other componentry in the area behind the instrument panel. The use of a slack absorbing apparatus introduces additional complexity, size, weight and cost to the wire harness unit.